Railway-traffic-controlling apparatus



July 7, 1925.

R. A. M CANN RAILWAY TRAFFIC CONTROLLING APPARATUS Filed May 16. 1923INVENTOR 2 H-Q. ATTORNEY Patented July 7, 1925.

UNITE- STARS P'ATENT ()F'EIGE.

RONALD A. McC-ANN, OF. SWISSVAL E, PENNSYLVANIA, ASSIG-NOR TO THE- UNIONSWITCH & SIGNAL COMPANY,-- OF SWISSVALE, -lENNSYLVANIA, A CORPORATION OF.IPENNSYLVANIA.

RAILWAY-TRAFFIC-CONTR-OLLING APPARATUS.

Application filed May'16;1923. Serial N0u639}336- 7 '0 all tUl'L-O'flbit may concern Be it known that I, RONALD A; MCCANN, a citizen of theUnited States,- residing at Swissvale, in the county of Allegheny andState of Pennsylvania, have invented certain new and usefulln'iprovements in Railway-lratiic-Gontrollmg Apparatus, of which thefollowing is a specification.

My invention relates to railway trafiic controlling apparatus, andparticularly to apparatus of the type comprising train carried governingmeans controlled by energy received from the trackway. Moreparticularly, my invention relates to the track-' way portion of suchapparatus.

1 will describe two forms and arrangements of railway trafficcontrolling apparatus embed m in invention and will then point out thenovel features thereof in claims.

in the accompanying drawings Fig. l is a diagrammatic view showing oneform of.

apparatus en'ihodyinp my invention. Fig. 2 is a view showing onemodification of the apparatus shown in Fig. 1 and also e1nbodymg myinvention.

Similar reference characters refer to similar parts in both views.

Referring first to Fig. 1, the reference characters 1 and l designatethe track rails of a railway over which tra-flic normally moves in thedirection indicated by the arrow. These track rails are divided by meansof insulated joints 2 into a plurality ofsuccessive track sections AB,'B-C, etc. Each such section is'provided with a source of track circuitcurrent which comprises, as shown in the drawing, a track transformerdesignated by thereference char-actor T with an exponent correspondingto the location and having its secondary 7 connected across the railsadjacent tho'exit end of the section and its primary 8 constantlysupplied withalternatirrc current from a generator N over line wires 3.interposed between each track transformer T and one rail 1 of the assoeiated section is an impedance 9, one function of which is to limit theoutput of the transformer when its terminals are short cireluted by thewheels and axles of a train. Each section is further provided with atrack relay designated by the reference character R with an exponentcorresponding to the loca ion, and provided with two windings 10 and 11.One winding 10 of each track relay R is constantly connected across therails adjacent :the entrance end of the associated section. Each tracksection is thus provided with a track circuitwhich comprisesthe=sec0ndary of a. trackitramsformer '1, a winding 10 of. a track'relay R and the two rails of the sectionein series.

Means are also providecl fon supplying-to the rails inparal'lehof; eachsection. an alternating current which I' sh'allu hereinafter term a:local current. For this purpose each section: is providedwithanimpedance connected across thetra'ils adi acentthe' entrance end of' thesection, a similar impedance 6 connected across the rails adjacentthe-exit end of the section, and arthirdsimilar impedance 5 connectedaorossthe. rails at an intermediate point in the section. The localcurrent for each section-- iszxsuip-plied from a locail transformerdesignated by the reference character E Withzan'exponent correspondingto the locationyand the primary windi n51 26 of=each-local transformer:is corn stant'ly supplied with alternating: current from a linetransformer'desi'ginated; by the reference character M nith amexponentcorresponding to the location. Each-such: line transformer M 18constantly supplied with alternating current over liner wires 3fr.om

the "generator N.

Referring particularly to section AB,

- one-local circuit :passes from: secondary 27 of: local -transforiner'E through front point of contact 12 of'track relay R wire 13, impedance6 in section A-.B, through both rails in parallelto impedance 4, thencethrough wire 14,-win.ding 11 0f track relay R wire lfnand frontpointof-contact 16 of track relay R, to seco-ndary27of' transformer E'lhiszcirciuit is closed'only when track relay R rsrenergrzed When thisre- Hil normal relative polarity) from the entrance end to the exit endof the section, or of the other relative polarity (which I shall termreverse relative polarity) between the entrance end and an intermediatepoint in the section, depending upon whether the track relay for thesection next in advance is energized or deenergized. Under either ofthese conditions, however, it will be noticed that winding 11 of thetrack relay for the associated section is included in the local circuit.Each track relay is so designed that for the relay to become energizedin such manner as to close its front contacts, both windings 10 and 11must be energized. It will then be plain that each track relay will beenergized only when its associated section is supplied with trackcircuit current and also with local current.

Located adjacent the entrance end of each section is a signal designatedby the reference character S with an exponent corresponding to thelocation, and each of which signals, in the form here shown, is of thethree-position semaphor type capable of indicating stop, caution andproceed. Each signal is provided with a circuit controller designated bythe reference character J with the same exponent as that applied to thesignal. Each signal is also provided with a caution circuit which isclosed only when the associated track relay is energized. Consideringsignal S, for example, this circuit passes from the secondary winding oftransformer M through wire 18, front contact 19 of track relay R wire20, operating" mechanism of signal S and wire 21 back to transformer MEach signal is also pro vided with a proceed circuit which is closedonly when the associated track relay is en ergized and the signal nextin advance in die-ates proceed or caution. Considering signal S, forexample, the proceed circuit passes from the secondary of transformer Mthrough wire 23, contact 24 of circuit controller J operated by signal swire 25, front contact 28 of track relay R wire 29, operating mechanismof signal S and wires 21 and 22 back to transformer M Before explainingthe operation of the apparatus it should be understood that the trackwayapparatus herein shown and de scribed is capable of co-op-eration withtraincarried governing apparatus in the following manner: When the trainoccupies a stretch of track which is supplied with track circuit currentand with local current of normal relative polarity, the govern ingapparatus gives a proceed indication on the train: when the train is ona stretch of track which is supplied with local current and also withtrack circuit current the rela tive polarity of either of which isreversed, the governing apparatus give a caution indication; and whenthe train occupies a stretch of track to which the supply of eitherlocal current or track circuit current is for any reason discontinued,the governing apparatus gives a stop indication.

As shown in the drawing, the parts of the apparatus are in normalpositions, that is, the positions they occupy when not influenced by thepresence of a train or trains. Under these circumstances each track section is supplied throughout its length with track circuit current andwith local current of normal relative polarity. All track relays R are,therefore, energized and each of the signals S displays a proceedindication.

I will now assume that a train occupies the section to the right ofpoint C. The consequent shunting of winding 10 of track rclay R causesthis relay to become de-energized, thus allowing signal S to display astop indication, thereby opening contact 24: of signal. circuitcontroller J The closing of the back contacts of relay R causes localcurrent of reverse relative polarity to be supplied to the rails ofsection BC between inipedances 4 and 5. Relay R is therefore energizedand signal S displays a caution indication, its proceed circuit havingbeen opened by circuit controller J Local current of normal relativepolarity is supplied to section AB between impedances 4. and 6 andsignal S is at proceed. The section to the left of point A is suppliedwith track circuit current and local current of normal relative polarityin a manner similar to section A--ll. t is clear that a second trainmoving in the direction of the arrow will receive a proceed llldltfibtion until it reaches point B. Between point v and impedance 5 insection B--C, the train will receive a caution indication due to thereversal of the local current in this portion of track. Betweenimpedance 5 and point C, the train will receive a stop indication as aresult of the interruption of local current in this portion of track,and this stop indication will, continue from point. C as far as thetrain which is occupying the section to the right of C, because of theabsence of track circuit current in this portion of track.

It will be observed that if for any reason the local circuit of asection is broken so that the supply of local current to that section isinterrupted, the associated track relay R is tie-energized and thesignal controlled there by is therefore allowed to display a stopindication. This control renders it impossible for a signal to display aproceed or caution indication unless the corresponding local and trackcircuit currents are being supplied to the section which it governs.Another advantage of this arrangement of apparatus is that if thereexists in the rails a foreign local current which tends to counofcircuit controller/L operated by signal mmom teract the normallocal-current, and it the magnitude of this foreign current issutiicicnt to render unreliable the operation of the governing mechanismbyneducing the ettcctive local current, this reduction will also operateto (lo-energize the associated track relay andwill tl'ierehyplace thecorresponding signal at. stop.

Referring now to Fig. 2,'eachtrack relay It comprises only one Winding10;ancl this winding is constantly connected across the rails adjacent.the entrance end of" the associated section. Each such relay isresponsive to reversals in the relative polarity of the current suppliedthereto. The primary 8 of each tach transformer 'P is supplied withalternating current of one relative po passes from secondary winding 27of local" transformer E through wire 30. contact tin--41? of circuitcontroller L ope 'ated by signal S. wire 31, impedance 6 of section B.through both, rails of the sect-ion in parallel to impedance wire 32',winding of relay K. and wire 233 back to t ranstormr E. This circuit isclosed when signal-*9 is at; proceed or aution. under which conditionsl: .Jl current of normal relative polarity is supplied to the rails ofsection A -B throughout, their ength. Vhen ,signahS displays a stopindication the closing of contact SE -3t) of signal. circuit controllerL completes a second local circuit and current lows from secondary 27ot'local trans former ll" through wire. 30, contact 6 5%, wire impedance 5in sectiou.i\-B, through both rails in parallel to impedance 4. wire 32.wind ng oF relay K". and wire 33.

back to transformer E thus sup ilying local current ot reverse relativepolarity to that portion of section A n which lies l)h\V01l impcdances land It will he noted that each of these local circuits includes theauxiliary relay K llach signal S is controlled by the associated trackrelay R and auxiliary relay K.

Referring particuhn'ly to section B-C audsignalv for governing trattictherethrough, when signal S indicates .caution or prol. track circuitcurrent of one relative ccc-z maritr, which I shall ter1 n.uo1:!nal.relathe polarity is supplied to the rails of sew Associated with eachsec-- tio1=r-B- C. "Relay R is therefore energized in the normaldirection aml'current flows from the secondary of line trans'tiormerll". through wires 3G-and 3:7, trout. contact 38 ot relay-K wire 39,normal contact of relay R wire -11, operating mechanism signal S 1 wire43, normal contact of relay'lW. wire 45, front conta t- 46 'of relay Kand wire 47 back to the secondary of transformer M thus causing signal Sto display a proceed in di'cation. The caution circuit for signal S isalso controlled by relay K and passes from the secondary of linetransformer M l througlr wires 36 and 37. front contact 3d relay l twire42 operating mechanism Signahtd", wire 4:3, reverse contact "24- o trackrelay R. wire 4-1 trout. contact of relay K and wire 47 back to thesecondary of transtormer M. This circuit closed only when relay K isenergized and relay R is energized in the reverse direct ion under whichcondition signal 9:" displays a caution indication. It is clear thatthe. failure of the local circuit for a section will die-energize theassociated relay K and :ause the associated signal to display a stopindi cation.

"Brains. passing through the stretch of track shown in Fig. 2 aregoverned in precisely the same manner as explained in cou nection withFig. l. with the single cxceg tion that the caution indication is causedin Fig; 2 by reversing the relative polarity of the-track circuitcurrent. whereas this accomplished in Fig, lby reversing the relativepolarity of the local current.

.tl't-hough I have herein shown and sle-- scribed only two terms ofrailway trattic controlling a 'rp-aratus embodying my invcut toil it ismiderstood that various changes and modifications may he made thereinwith n the scope of the appended claims without departiug'from thespirit and scope of my invention.

Having thus described my invention wha I claim is:

1. Railway tratlic controllii'ig apparatus comprising a section ofrailway track. sigual for said section tor at times displaying a morerestrictive indication, means t'or supplying local currentto the railsof said section in parallel; and m ans for causing said signal todisplaya less restrictive indi cation only when such means is operative.

In combination. a sectionot railway track, means for supplying analternating of relay K, wire 3%), reverse contact H) t t current to therails=of said section in parallel. a signal for said section and meaufor causing said signal to display a restricti-veindication whensuchsupply is interrupted.

3. In combination. a section of railway track, a signal tor said sectionresponsive to traliic conditions in said section, means tor supplying analternating current to the rails of said section in parallel, and meansfor causing said signal to display a restrictive indication when saidsupply is interrupted.

4. In combination, a section of railway track, a track circuit for saidsection including the rails of said section in series, a signal for saidsection controlled by said track circuit, an auxiliary circuit includingthe rails oi said section in parallel, and means for operating saidsignal only when said auxiliary circuit is complete.

In combination, a section of railway track, a source of track circuitcurrent for said section. a track relay for said section, a signalcontrolled by said track relay, an auxiliary circuit including the railsof said section in parallel, and means for operating said signal onlywhen said auxiliary circuit is complete.

6. In combination, a section of railway track. a signal for said sectionfor at. times displaying one indication, means for causing said signalto display a different indication when said section is occupied by atrain, means for supplying a current to the rails of said section inparallel, and means for causing said signal, to display said differentindication when such supply is ineffective, irrespective of traflicconditions in said section.

7. In combination, a section of railway track. means for supplying therails \of said section with track circuit and also with local currentwhich traverses the rails of the section in parallel, and traclcwaysignaling means controlled jointly by said two currents.

8. In combination, a section of railway track, means for supplying saidsection with track circuit current, means for supplying the rails ofsaid section in parallel with 10- cal current, a relay controlled bysaid two currents, and signaling means controlled by said relay.

9., In combination, a section of railway track. a local circuitincluding at least one rail of said section, a track circuit for saidsection, a relay having two windings one included in each said circuit,and signaling means controlled by said relay.

10. In combination, a plurality of successive sections of railway track,a relay for each section having two windings, means responsive totraffic conditions in each section for supplying one winding of theassociated relay with track circuit current, means controlled by eachsuch relay for supplying local current to the track rails of the sectionnext in rear, and to the remaining winding of the relay associated withsuch section, and traffic controlling apparatus controlled by each saidrelay.

11. In combination, a plurality of successive sections of railway track,a relay for each section having two windings, means responsive totraffic conditions in each section for supplying one winding of theassociated relay with track circuit current, means controlled by eachsuch relay for supplying local current to the track rails of the sectionnext in rear and to the remaining winding of the relay associated withsuch section, a signal ,for each section biased to give a morerestrictive indication, and means for causing each such signal todisplay a less restrictive indication only when both windings of theassociated track relay are energized.

12. In combination, a section of railway track, a relay for saidsection, a track circuit for said section including one winding of saidrelay, two local circuits for supplying the track rails of said sectionwith local current of one or the other relative polarity, respectively,a second winding of said relay included in both said local circuits, andtrafiic controlling apparatus controlled by said relay.

13. In combination, a section of railway track, a plurality of localcircuits for said section each including a portion of at least one railof the section. a relay included in all said local circuits and trafliccontrolling means controlled by said relay.

14. In combination, a section of railway track, means for supplyingtrain controlling current to the rails of said section in parallel, anda signal for said section controlled in part by said train controllingcurrent.

15. In combination, a section of railway track, means for supplyingtrain controlling current to the rails of said section in parallel, andmeans for giving a stop indication to a train approaching said sectionin the event of abnormal reduction of said train controlling current.

16. In combination, a section of railway track, a track circuit for saidsection including a source of alternating current and a track relayhaving a track winding and a local winding, a local circuit for saidlocal winding including the rails of the section in multiple and asource of alternating current, and means controlled bv traflic conditions in advance of said section for reversing the instantaneousrelative polarity of the currents in said two circuits.

17. In combination, a section of railway track, a track circuit for saidsection including a source of alternating current and a track relayhaving a. track winding and a local winding, and means controlled bytraffic conditions in advance of said section for supplying alternatingcurrent of one instantaneous relative polarity or the other to the localwinding of said relay and to the track rails of the section in multiple.

18. In combination, a section of railway track, a relay for said sectionhaving a track winding and a local winding, means for supplyingalternating track circuit current to the track winding of said relay,means for supplying alternating local current to the local winding ofsaid relay and to the rails of said section in multiple, and meansgoverned by traflic conditions in advance of said section for reversingthe instantaneous relative polarity of said currents.

19. In combination, a section of railway track, a relay for said sectionhaving, two co-operating windings, means for supplying alternatingcurrent to one winding: of said relay, means for supplying anotheralternating current to the other winding of said relay and to the railsof said section in multiple, and means governed by traffic conditions inadvance of said section for reversing the instantaneous relativepolarity of said currents.

20. In combination, a section of railway track, a relay for said sectionhaving two co-operating windings, means for supplying an alternatingcurrent to one Winding of said relay, and means controlled by traflicconditions in advance of said section for supplying alternating currentof one instan taneous relative polarity or the other to the otherwinding of said relay and to the two rails of said section in multiple.

21. I11 combination, a section of railway track, arelay for said sectionhaving two co-operatingr windings, means for supplying one alternatingcurrent to one winding of said relay, and means controlled by tratlicconditions in advance of said section for supplying another alternatingcurrent to the other winding of said relay and to the rails of thesection in multiple and for reversing the instantaneous relativepolarity of such second current.

22. In combination, a section of railway track, means for applying analternating difference of potential across the rails of said section, arelay having two windings one of which is connected across the rails ofsaid section, and means for applying a second alternating difference ofpotential of one relative polarity or the other along the rails of saidsection and to the second winding of said relay.

In testimony whereof I aflix my signature.

RONALD A. MCUAN

